fix(oom): Improve background app state detection

CHANGELOG.md

@@ -1,8 +1,21 @@
 Changelog
 =========
 
+## TBD
+
+### Bug fixes
+
 * Support adding pre-delivery metadata to out-of-memory reports
   [#393](https://github.com/bugsnag/bugsnag-cocoa/pull/393)
+* Fix erroneously reporting out-of-memory events from iOS app extensions
+  [#394](https://github.com/bugsnag/bugsnag-cocoa/pull/394)
+* Fix erroneously reporting out-of-memory events when an iOS app is in the
+  foreground but inactive
+  [#394](https://github.com/bugsnag/bugsnag-cocoa/pull/394)
+* Fix erroneously reporting out-of-memory events when the app terminates
+  normally and is issued a "will terminate" notification, but is terminated
+  prior to the out-of-memory watchdog processing the notification
+  [#394](https://github.com/bugsnag/bugsnag-cocoa/pull/394)
 
 ## 5.22.3 (2019-07-15)
 

CONTRIBUTING.md

@@ -89,6 +89,7 @@ Run the integration tests using `make e2e` (end-to-end)
   - [ ] Have the changelog and README been updated?
   - [ ] Are there pull requests for installation changes on the [dashboard](https://github.com/bugsnag/dashboard-js)?
   - [ ] Are there pull requests for new features/behavior on the [docs site](https://github.com/bugsnag/docs.bugsnag.com)?
+  - [ ] Run `./Tests/prerelease/run_prerelease_checks.sh`
   - [ ] Has all new functionality been manually tested on a release build?
   - [ ] Do the installation instructions work when creating an example app from scratch?
   - [ ] If a response is not received from the server, is the report queued for later?

Source/BSGOutOfMemoryWatchdog.m

@@ -63,6 +63,14 @@ - (void)enable {
                selector:@selector(handleTransitionToForeground:)
                    name:UIApplicationWillEnterForegroundNotification
                  object:nil];
+    [center addObserver:self
+               selector:@selector(handleTransitionToActive:)
+                   name:UIApplicationDidBecomeActiveNotification
+                 object:nil];
+    [center addObserver:self
+               selector:@selector(handleTransitionToInactive:)
+                   name:UIApplicationWillResignActiveNotification
+                 object:nil];
     [center addObserver:self
                selector:@selector(handleLowMemoryChange:)
                    name:UIApplicationDidReceiveMemoryWarningNotification
@@ -114,6 +122,17 @@ - (void)observeValueForKeyPath:(NSString *)keyPath
     self.cachedFileInfo[@"app"][@"releaseStage"] = change[NSKeyValueChangeNewKey];
     [self writeSentinelFile];
 }
+
+- (void)handleTransitionToActive:(NSNotification *)note {
+    self.cachedFileInfo[@"app"][@"isActive"] = @YES;
+    [self writeSentinelFile];
+}
+
+- (void)handleTransitionToInactive:(NSNotification *)note {
+    self.cachedFileInfo[@"app"][@"isActive"] = @NO;
+    [self writeSentinelFile];
+}
+
 - (void)handleTransitionToForeground:(NSNotification *)note {
     self.cachedFileInfo[@"app"][@"inForeground"] = @YES;
     [self writeSentinelFile];
@@ -154,6 +173,8 @@ - (BOOL)computeDidOOMLastLaunchWithConfig:(BugsnagConfiguration *)config {
                 [lastBootInfo valueForKeyPath:@"device.osBuild"];
             BOOL lastBootInForeground =
                 [[lastBootInfo valueForKeyPath:@"app.inForeground"] boolValue];
+            BOOL lastBootWasActive =
+                [[lastBootInfo valueForKeyPath:@"app.isActive"] boolValue];
             NSString *osVersion = [BSG_KSSystemInfo osBuildVersion];
             NSDictionary *appInfo = [[NSBundle mainBundle] infoDictionary];
             NSString *bundleVersion =
@@ -163,7 +184,8 @@ - (BOOL)computeDidOOMLastLaunchWithConfig:(BugsnagConfiguration *)config {
             BOOL sameVersions = [lastBootOSVersion isEqualToString:osVersion] &&
                                 [lastBootBundleVersion isEqualToString:bundleVersion] &&
                                 [lastBootAppVersion isEqualToString:appVersion];
-            BOOL shouldReport = config.reportOOMs && (config.reportBackgroundOOMs || lastBootInForeground);
+            BOOL shouldReport = config.reportOOMs
+                && (config.reportBackgroundOOMs || (lastBootInForeground && lastBootWasActive));
             [self deleteSentinelFile];
             return sameVersions && shouldReport;
         }
@@ -221,7 +243,24 @@ - (NSMutableDictionary *)generateCacheInfoWithConfig:(BugsnagConfiguration *)con
     app[@"releaseStage"] = config.releaseStage;
     app[@"version"] = systemInfo[@BSG_KSSystemField_BundleShortVersion] ?: @"";
     app[@"bundleVersion"] = systemInfo[@BSG_KSSystemField_BundleVersion] ?: @"";
+#if BSGOOMAvailable
+    UIApplicationState state = [self currentAppState];
+    // The app is in the foreground if the current state is "active" or
+    // "inactive". From the UIApplicationState docs:
+    // > UIApplicationStateActive
+    // >   The app is running in the foreground and currently receiving events.
+    // > UIApplicationStateInactive
+    // >   The app is running in the foreground but is not receiving events.
+    // >   This might happen as a result of an interruption or because the app
+    // >   is transitioning to or from the background.
+    // > UIApplicationStateBackground
+    // >   The app is running in the background.
+    app[@"inForeground"] = @(state == UIApplicationStateInactive
+                          || state == UIApplicationStateActive);
+    app[@"isActive"] = @(state == UIApplicationStateActive);
+#else
     app[@"inForeground"] = @YES;
+#endif
 #if TARGET_OS_TV
     app[@"type"] = @"tvOS";
 #elif TARGET_IPHONE_SIMULATOR || TARGET_OS_IPHONE
@@ -246,4 +285,17 @@ - (NSMutableDictionary *)generateCacheInfoWithConfig:(BugsnagConfiguration *)con
     return cache;
 }
 
+// Only available on iOS/tvOS
+#if BSGOOMAvailable
+- (UIApplicationState)currentAppState {
+    // Only checked outside of app extensions since sharedApplication is
+    // unavailable to extension UIKit APIs
+    if ([BSG_KSSystemInfo isRunningInAppExtension]) {
+        return UIApplicationStateActive;
+    }
+    UIApplication *app = [UIApplication performSelector:@selector(sharedApplication)];
+    return [app applicationState];
+}
+#endif
+
 @end

Source/BugsnagBreadcrumb.h

@@ -129,9 +129,4 @@ typedef void (^BSGBreadcrumbConfiguration)(BugsnagBreadcrumb *_Nonnull);
  */
 - (NSArray *_Nullable)arrayValue;
 
-/**
- * Reads and return breadcrumb data currently stored on disk
- */
-- (NSDictionary *_Nullable)cachedBreadcrumbs;
-
 @end

Source/BugsnagBreadcrumb.m

@@ -233,8 +233,8 @@ - (void)addBreadcrumbWithBlock:
     }
 }
 
-- (NSDictionary *)cachedBreadcrumbs {
-    __block NSDictionary *cache = nil;
+- (NSArray *)cachedBreadcrumbs {
+    __block NSArray *cache = nil;
     dispatch_barrier_sync(self.readWriteQueue, ^{
         NSError *error = nil;
         NSData *data = [NSData dataWithContentsOfFile:self.cachePath options:0 error:&error];
@@ -245,7 +245,7 @@ - (NSDictionary *)cachedBreadcrumbs {
             bsg_log_err(@"Failed to read breadcrumbs from disk: %@", error);
         }
     });
-    return cache;
+    return [cache isKindOfClass:[NSArray class]] ? cache : nil;
 }
 
 @synthesize capacity = _capacity;

Source/BugsnagNotifier.m

@@ -27,6 +27,7 @@
 #import "BugsnagNotifier.h"
 #import "BSGConnectivity.h"
 #import "Bugsnag.h"
+#import "Private.h"
 #import "BugsnagCrashSentry.h"
 #import "BugsnagHandledState.h"
 #import "BugsnagLogger.h"
@@ -36,6 +37,7 @@
 #import "BSG_RFC3339DateTool.h"
 #import "BSG_KSCrashType.h"
 #import "BSG_KSCrashState.h"
+#import "BSG_KSSystemInfo.h"
 #import "BSG_KSMach.h"
 
 #if TARGET_IPHONE_SIMULATOR || TARGET_OS_IPHONE
@@ -387,7 +389,16 @@ - (void)start {
 #endif
 
     _started = YES;
-    if (self.configuration.reportOOMs && !bsg_ksmachisBeingTraced() && self.configuration.autoNotify) {
+    // autoNotify disables all unhandled event reporting
+    BOOL configuredToReportOOMs = self.configuration.reportOOMs && self.configuration.autoNotify;
+    // Disable if a debugger is enabled, since the development cycle of starting
+    // and restarting an app is also an uncatchable kill
+    BOOL noDebuggerEnabled = !bsg_ksmachisBeingTraced();
+    // Disable if in an app extension, since app extensions have a different
+    // app lifecycle and the heuristic used for finding app terminations rooted
+    // in fixable code does not apply
+    BOOL notInAppExtension = ![BSG_KSSystemInfo isRunningInAppExtension];
+    if (configuredToReportOOMs && noDebuggerEnabled && notInAppExtension) {
         [self.oomWatchdog enable];
     }
 
@@ -579,16 +590,29 @@ - (void)notifyOutOfMemoryEvent {
     static NSString *const BSGOutOfMemoryErrorClass = @"Out Of Memory";
     static NSString *const BSGOutOfMemoryMessageFormat = @"The app was likely terminated by the operating system while in the %@";
     NSMutableDictionary *lastLaunchInfo = [[self.oomWatchdog lastBootCachedFileInfo] mutableCopy];
-    BOOL wasInForeground = [[lastLaunchInfo valueForKeyPath:@"app.inForeground"] boolValue];
-    NSString *message = [NSString stringWithFormat:BSGOutOfMemoryMessageFormat, wasInForeground ? @"foreground" : @"background"];
-    BugsnagHandledState *handledState = [BugsnagHandledState
-        handledStateWithSeverityReason:LikelyOutOfMemory
-                              severity:BSGSeverityError
-                             attrValue:nil];
-    NSDictionary *crumbs = [self.configuration.breadcrumbs cachedBreadcrumbs];
+    NSArray *crumbs = [self.configuration.breadcrumbs cachedBreadcrumbs];
     if (crumbs.count > 0) {
         lastLaunchInfo[@"breadcrumbs"] = crumbs;
     }
+    for (NSDictionary *crumb in crumbs) {
+        if ([crumb isKindOfClass:[NSDictionary class]]
+            && [crumb[@"name"] isKindOfClass:[NSString class]]) {
+            NSString *name = crumb[@"name"];
+            // If the termination breadcrumb is set, the app entered a normal
+            // termination flow but expired before the watchdog sentinel could
+            // be updated. In this case, no report should be sent.
+            if ([name isEqualToString:kAppWillTerminate]) {
+                return;
+            }
+        }
+    }
+
+    BOOL wasInForeground = [[lastLaunchInfo valueForKeyPath:@"app.inForeground"] boolValue];
+    NSString *message = [NSString stringWithFormat:BSGOutOfMemoryMessageFormat, wasInForeground ? @"foreground" : @"background"];
+    BugsnagHandledState *handledState = [BugsnagHandledState
+                                         handledStateWithSeverityReason:LikelyOutOfMemory
+                                         severity:BSGSeverityError
+                                         attrValue:nil];
     NSDictionary *appState = @{@"oom": lastLaunchInfo, @"didOOM": @YES};
     [self.crashSentry reportUserException:BSGOutOfMemoryErrorClass
                                    reason:message

Source/KSCrash/Source/KSCrash/Recording/BSG_KSSystemInfo.h

@@ -73,4 +73,9 @@
  */
 + (NSString *)osBuildVersion;
 
+/**
+ * Whether the current main bundle is an iOS app extension
+ */
++ (BOOL)isRunningInAppExtension;
+
 @end

Source/KSCrash/Source/KSCrash/Recording/BSG_KSSystemInfo.m

@@ -433,6 +433,26 @@ + (NSString *)osBuildVersion {
     return [self stringSysctl:@"kern.osversion"];
 }
 
++ (BOOL)isRunningInAppExtension {
+#if BSG_KSCRASH_HOST_IOS
+    NSBundle *mainBundle = [NSBundle mainBundle];
+    // From the App Extension Programming Guide:
+    // > When you build an extension based on an Xcode template, you get an
+    // > extension bundle that ends in .appex.
+    return [[mainBundle executablePath] containsString:@".appex"]
+        // In the case that the extension bundle was renamed or generated
+        // outside of the Xcode template, check the Bundle OS Type Code:
+        // > This key consists of a four-letter code for the bundle type. For
+        // > apps, the code is APPL, for frameworks, it's FMWK, and for bundles,
+        // > it's BNDL.
+        // If the main bundle type is not "APPL", assume this is an extension
+        // context.
+        || ![[mainBundle infoDictionary][@"CFBundlePackageType"] isEqualToString:@"APPL"];
+#else
+    return NO;
+#endif
+}
+
 @end
 
 const char *bsg_kssysteminfo_toJSON(void) {

Source/Private.h

@@ -0,0 +1,13 @@
+#ifndef BUGSNAG_PRIVATE_H
+#define BUGSNAG_PRIVATE_H
+
+#import "BugsnagBreadcrumb.h"
+
+@interface BugsnagBreadcrumbs ()
+/**
+ * Reads and return breadcrumb data currently stored on disk
+ */
+- (NSArray *_Nullable)cachedBreadcrumbs;
+@end
+
+#endif // BUGSNAG_PRIVATE_H

Tests/prerelease/features/out_of_memory.feature

@@ -0,0 +1,12 @@
+Feature: Out of memory events
+
+    Scenario: The OS kills the application while inactive
+        The application is in the foreground but inactive when interrupted 
+        by a phone call or Siri
+
+        When I run "OOMScenario"
+        And the app is interrupted by Siri
+        And the app is unexpectedly terminated
+        And I relaunch the app
+        And I wait for 10 seconds
+        Then I should receive 0 requests

Tests/prerelease/run_prerelease_checks.sh

@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+
+# Run visibly to allow scripting access (pressing buttons, etc)
+open $(xcode-select -p)/Applications/Simulator.app
+
+bundle exec maze-runner Tests/prerelease/features/

features/fixtures/ios-swift-cocoapods/iOSTestApp.xcodeproj/project.pbxproj

@@ -81,6 +81,8 @@
 		8A32DB8122424E3000EDD92F /* NSExceptionShiftScenario.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = NSExceptionShiftScenario.m; sourceTree = "<group>"; };
 		8A42FD33225DEE04007AE561 /* SessionOOMScenario.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SessionOOMScenario.m; sourceTree = "<group>"; };
 		8A42FD34225DEE04007AE561 /* SessionOOMScenario.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SessionOOMScenario.h; sourceTree = "<group>"; };
+		8A56EE7F22E22ED80066B9DC /* OOMWillTerminateScenario.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = OOMWillTerminateScenario.m; sourceTree = "<group>"; };
+		8A56EE8022E22ED80066B9DC /* OOMWillTerminateScenario.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = OOMWillTerminateScenario.h; sourceTree = "<group>"; };
 		8A840FB921AF5C450041DBFA /* SwiftAssertion.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SwiftAssertion.swift; sourceTree = "<group>"; };
 		8A98400120FD11BF0023ECD1 /* AutoSessionCustomVersionScenario.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = AutoSessionCustomVersionScenario.h; sourceTree = "<group>"; };
 		8A98400220FD11BF0023ECD1 /* AutoSessionCustomVersionScenario.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = AutoSessionCustomVersionScenario.m; sourceTree = "<group>"; };
@@ -233,6 +235,8 @@
 		F42953DE2BB41023C0B07F41 /* scenarios */ = {
 			isa = PBXGroup;
 			children = (
+				8A56EE8022E22ED80066B9DC /* OOMWillTerminateScenario.h */,
+				8A56EE7F22E22ED80066B9DC /* OOMWillTerminateScenario.m */,
 				8A14F0F42282D4AE00337B05 /* ReportBackgroundOOMsEnabledScenario.h */,
 				8A14F0F02282D4AD00337B05 /* ReportBackgroundOOMsEnabledScenario.m */,
 				8A14F0EF2282D4AD00337B05 /* ReportOOMsDisabledReportBackgroundOOMsEnabledScenario.h */,
@@ -446,6 +450,7 @@
 				F42955E0916B8851F074D9B3 /* UserEmailScenario.swift in Sources */,
 				F4295968571A4118D6A4606A /* UserEnabledScenario.swift in Sources */,
 				F4295A036B228AF608641699 /* UserDisabledScenario.swift in Sources */,
+				8A56EE8222E22ED80066B9DC /* OOMWillTerminateScenario.m in Sources */,
 				8A14F0F62282D4AE00337B05 /* ReportOOMsDisabledScenario.m in Sources */,
 				E7767F13221C21E30006648C /* ResumedSessionScenario.swift in Sources */,
 				8AEFC73120F8D1A000A78779 /* AutoSessionWithUserScenario.m in Sources */,

features/fixtures/ios-swift-cocoapods/iOSTestApp/scenarios/OOMWillTerminateScenario.h

@@ -0,0 +1,5 @@
+#import "Scenario.h"
+
+@interface OOMWillTerminateScenario : Scenario
+
+@end

features/fixtures/ios-swift-cocoapods/iOSTestApp/scenarios/OOMWillTerminateScenario.m

@@ -0,0 +1,18 @@
+
+#import "OOMWillTerminateScenario.h"
+#import <signal.h>
+#import <UIKit/UIKit.h>
+
+@implementation OOMWillTerminateScenario
+
+- (void)startBugsnag {
+    self.config.shouldAutoCaptureSessions = NO;
+    [super startBugsnag];
+}
+
+- (void)run {
+    dispatch_async(dispatch_get_main_queue(), ^{
+        exit(0);
+    });
+}
+@end

features/out_of_memory.feature

@@ -21,6 +21,28 @@ Feature: Reporting out of memory events
         And the event "metaData.extra.shape" equals "line"
         And the event breadcrumbs contain "Crumb left before crash"
 
+    Scenario: The app is terminated normally
+        The application can be gracefully terminated by the OS if more
+        memory is needed for other applications or directly by calling
+        exit(0)
+
+        When I crash the app using "OOMWillTerminateScenario"
+        And I wait for 4 seconds
+        And I relaunch the app
+        And I wait for 10 seconds
+        Then I should receive 0 requests
+
+    Scenario: The app is terminated normally
+        The application can be gracefully terminated by the OS if more
+        memory is needed for other applications or directly by calling
+        exit(0)
+
+        When I crash the app using "OOMWillTerminateScenario"
+        And I wait for 4 seconds
+        And I relaunch the app
+        And I wait for 10 seconds
+        Then I should receive 0 requests
+
     Scenario: The OS kills the application in the background
         When I run "OOMScenario"
         And I put the app in the background

features/scripts/activate_siri.sh

@@ -0,0 +1,17 @@
+#!/usr/bin/env osascript
+
+tell application "Simulator"
+    activate
+end tell
+
+tell application "System Events"
+    tell process "Simulator"
+        tell menu bar 1
+            tell menu bar item "Hardware"
+                tell menu "Hardware"
+                    click menu item "Siri"
+                end tell
+            end tell
+        end tell
+    end tell
+end tell